What if Elizabeth had come back? What if Samantha had stayed? What if John had been sleeping with both of them? John/Elizabeth. John/Samantha with eventual John/Elizabeth/Samantha. Doesn't have to be NC17 though if so it might just be the first for that particular threesome.
How about a Twilight crossover? 17 year old Meredith Rodney McKay goes to the town of Forks, Washington (for whatever reason the author chooses), and is instantly attracted to the mysterious 17 year old John Sheppard and his family. He doesn't know that they're vampires! John is like Edward: he can read people's minds, all except Rodney's. And Rodney is his Singer: his blood is more tempting to John than any others. You can have any of the other SGA or Sg1 characters in the story as John's family/foes, or you can use the Twilight characters, but replace Edward with John. But Ronan has to take the place of Jacob as a werewolf. The ending HAS to be either John/Rodney, or Rodney/Ronan. If you're up to it, I'm completely fine with John/Rodney/Ronan, but I strongly prefer McShep. :) Any characters from both SGA and SG1 are allowed, but this fic should be McShep centered! (Preferably in Rodney's perspective!)
Categories: Crossovers > Threesomes, Moresomes or Bitextual, Slash Pairings > McKay/Sheppard, Slash Pairings > McKay/Ronon Dex, Threesomes and Moresomes > Strictly slash Characters: Aiden Ford, Cameron Mitchell, Carson Beckett, Daniel Jackson, Elizabeth Weir, Jack O'Neill, Jennifer Keller, John Sheppard, Major Lorne, Original Character, Other, Radek Zelenka, Rodney McKay, Ronon Dex, Samantha Carter, Steven Caldwell, Teal'c, Teyla Emmagan, Vala Mal Doran